PROJECT SUMMARY: APPLIED RESEARCH COMPONENT The Squirrel Monkey Breeding and Research Resource (SMBRR), P40 OD010938 has received continuous NIH grant support since 1980. The SMBRR's proposed applied research projects include projects that will broaden the application and usefulness of the resource for the user community, as well as provide information that will allow for better management of the colony itself. Immunology research proposed will continue work from Dr. Nehete's lab on defining and characterizing the squirrel monkey immune system. This project will provide insights into the similarities and differences in squirrel monkey immune cells compared to those of human beings. Additionally, these studies will identify new reagents that cross react with squirrel monkey lymphocyte subsets and adjuvants that can be used to deliver vaccines. The gut microbiome study proposed will explore microbiome populations in squirrel monkeys of differing ages and sex. There is a growing body of evidence that changes in the gut microbiome can affect behavior, immune function, and emotional affect. This study will generate a preliminary, systematic map of GM taxonomic characteristics for age/sex classes in each Saimiri species as well as a comparison of gut microbiota traits in Saimiri species. This map will contribute to eliminating gaps in our knowledge of how GM composition varies among age/sex classes and host species and how this might affect the health of these species. The behavioral studies proposed complement an ongoing NIH funded project to study cerebral amyloid angiopathy in squirrel monkeys. They also represent the beginning of an effort to develop a behavioral phenotyping program as part of the SMBRR. All of the studies proposed in the Applied Research Component pursue scientific questions about squirrel monkey biology and behavior that will allow us to enhance the value of the resource.